Casing-shoe



I. G. LINDSAY.

cAslNG sHoE.

APPLICATION FILED MAY I6. 1918.

Patented Dec. 28,1920.

WMM. f5v

JOSEPH G. LINDSAY, OF BARTLESVILLE, OKLAHOMA.

v cAsING-sHoE.

Specification of Letters Patent.

Patented Dec. 28, 1920.

Application filed May 16, 1918. Serial No. 235,003.

T 0 all whom t may concern.'

Be it known that I, JOSEPH G. LiNDsAY, a citizen of the United States,residing at Bartlesville, in the county ofWashington and State ofOklahoma, have invented certain new and useful Improvements inCasing-Shoes; and I dodeclare the following to be a full, clear,andexact description of the invention, such as will enable othersskilled in the art to which it appertains to make and use the same.

My invention relates to improvements in shoes such as those used on thelower ends of oil well casings and the like to form a tight connectionbetween the casing and the internal ledge formed at the juncture of thetwo diameters of the well bore. The old form of shoe has been found tobe more or less ineiiicient since it provides 11o means to prevent theledge from crumbling and thus the casing is not only permitted togradually sink,- but a tightly packed joint cannot be maintained.

The present invention has for its object to overcome the difficultiesabove pointed out, by the provision of a simple and inexpensive device,and with this object in view, the invention resides in the novelfeatures of construction hereinafter fully described and claimed, thedescriptive matter being supplemented by the accompanying drawingforming a part of this application and in which:

Figure l is a vertical section of one form of the invention applied;

ig. 2 is a side elevation of the device shown in Fig. l; y y

Fig. 3 is a duplicate of Fig. 1 but showing a different form ofconstruction; and

Fig. 4 is a side elevation of the form of the device shown in Fig. 3.

In the drawings above briefly described, the numeral 1 designates thebore o f an oil well or the like which is counterbored at 2 to form aninternal annular ledge 3 at the juncture of the two well diameters. Itis upon this ledge that the shoe 4 of the well casing 5 is supported. l

The shoe 4 consists of a tubular body whose upper portion is ofsufficient internal diameter to permit the casing 5 to be passed easilyinto the same for engagement with the internal screw threads 6, wherebybody of the shoe is shown enlarged although this is AIlot altogethernecessary, and the lower end of the enlargement is beveled upwardly andinwardly to form an annular external shoulder 8 to rest on the ledge 3,thus supporting the casing and forming a seal between the same and thewall of the well bore.

The known to those skilled in the art, but has been found to be more orless inefficient since there is no provision made to prevent crumblingof the ledge 3, and consequent sinkage of the casing, as well as leakageof the joint. I overcome these diiiiculties however by the addition of atubular extension 9 on the lower end of the shoe, said extension beingpreferably formed integrally with the shoe and projecting below theshoulder 8 arrangement so far described is well for snug reception inthe smaller diameter A of the well bore as seen in Fig. l. Thisextensionnot only prevents caving or crumbling of the ledge 3, but formsan additional seal between the shoe and the wall of the well bore, theadvantages of which will be obvious to those skilled in theart. Itshould be noted that by having the extended lower end portion 9 of thisshoe of'even diameter throughout its length it may bev inserted into thereduced lower portion l of the well 2 and will have tight engagementrwith the walls of the well throughout its entire length thus preventingcaving in lof the walls of the well at the ledge 3.

In Figs. 3 and 4, the construction of the shoe 4a scribed, but theshoulder 8a is not as abrupt as the shoulder 8 and tapers downwardly andinwardly to the extension 9a. The operation alid advantages of this typeof the device are identical with those of the form above described, withthe exception that the shoulder 8a will have more of a packing effect onthe earth upon which it rests.

From the foregoing, taken in connection with the accompanying drawing,it will be obvious that although I have provided an extremely simple andinexpensive casing shoe, it will possess marked advantages over thedevices now commonly used. Since probably the best results are obtainedfrom the details shown and described, they are preferable, but withinthe scope of the invention as claimed,numerous minor changes may well bemade. to attach the shoe to the casing. At 7, the

I claim: 'A tubular casing shoe having its walls externally thickened ata point intermediate its height to provide a supporting collarfor wallsof the reduced lower end portion of a y engaging the annular supportingledge in well below the supporting ledge when the the lower portion of awell, the lower end Collar is resting upon the ledge. 10 portion of theshoe providing a sleeve of In testimony whereof I have hereunto set evenexternal diameter throughout its my hand,

length and adapted to t in tight engagement throughout its entirelengthwith the JOSEPH Gr. LINDSAY.

